| 摘要 |
PURPOSE:To supply a method and circuit for controlling series resonance convertors so that their efficiency does not lower even on a light load. CONSTITUTION:In a series resonance converter, a series resonance circuit consisting of circuit components equivalent to a resonance inductance 12 and resonance capacitor 13 is connected to the output of an inverter 2 comprising at least a pair of switching elements 3-6. The series resonance convertor rectifies the voltage across the capacitor 13 and outputs the rectified voltage. The switching elements 3-6 are controlled by pulse width modulation control and pulse frequency modulation control by applying the output signal of an error amplifier 19 that compares the output parameter with the reference value to a pulse width modulation circuit 29 and voltage controlled oscillator 23 that provides signals for the pulse width modulation circuit. |
